A million-in-one chance for the “Million Dollar Baby”?

Oscar-winner Hilary Swank recently announced she’s expecting her third baby later in December, adding to the growing list of women becoming pregnant during the transition to menopause.

While the 52-year-old actress is hardly the last woman to carry a child while approaching “The Change,” an expert breaks down what to know about the risks and possibilities.

Actress Hilary Swank recently announced she’s pregnant at 52 years old – the average age of menopause. GC Images

The average age of menopause in the US is 51 to 52 years old, with perimenopause (the transition years leading up to menopause) typically starting in a woman’s 40s.

Already a mom to 3-year-old twins, Swank joins several other women who became pregnant during perimenopause, though the odds drastically decrease as age increases.

In 2017, there were 840 births from women 50 years and older, with a birth rate of 0.8 births per 1,000 women aged 50 to 54, according to the National Center for Health Statistics.

Pregnancy during the menopause transition isn’t entirely impossible, either naturally or through in vitro fertilization (IVF), although there are risks, says Dr. Natasha Spencer, an obstetrician gynecologist at Orlando Health Physician Associates.

“If a woman is experiencing ovulation/cycling, although irregularly and/or sporadic, it is always possible to achieve pregnancy naturally — however, with a lower probability,” Spencer told The Post.

“Moreover, older women experience an increased rate of early pregnancy loss, both trisomic and euploid, primarily due to a decline in egg quality.”

While perimenopausal women can still get pregnant, the chances are small and come with several health risks. BACKGRID

Spencer also noted that changes in uterine and hormonal function play a role in pregnancy loss, with many occurring between six and 14 weeks of gestation.

Assisted reproductive technologies like IVF can provide older women more opportunities for pregnancy.

Preprocedural factors, though, can affect the success rate, such as “female age, type of infertility diagnosis and past reproductive-obstetric history,” Spencer said.

Reproductive procedures like in vitro fertilization may increase the odds of perimenopausal women becoming pregnant. Rene L/peopleimages.com – stock.adobe.com

While younger women are at risk for the same pregnancy complications as older women, the odds increase due to age and other factors.

Carrying multiple fetuses, a history of complicated pregnancies and health conditions like diabetes or high blood pressure can all increase the chances of complications throughout gestation.

And complications can occur for both mother and child.

Older moms-to-be are at risk for early pregnancy losses, ectopic pregnancies, placenta previa (when the placenta blocks the baby’s exit), protracted labor and severe maternal morbidity and mortality.

“Some fetal/neonatal risks include chromosomal and gene abnormalities, congenital malformations, low birth weight and preterm births and perinatal mortality,” Spencer added.

However, once the transition to menopause is complete — no menstrual cycle for a minimum of 12 months, plus symptoms like hot flashes and night sweats — there’s no possibility for pregnancy due to no more eggs present in the ovaries.

There is still a chance for perimenopausal or even menopausal women to carry a child “through assisted reproductive technologies via egg donors or embryos created by them earlier in life,” Spencer said.

There may be other benefits to pregnancy later in life as well.

“Most women of advanced age will ultimately have good pregnancy outcomes and are able to cope with the physical and emotional stresses of pregnancy and parenting better,” Spencer explained.

“Increasing maternal age may also be associated with improved health and development for young children.”